FORT HOOD, Texas — Pvt. Joseph Foster took a bullet in the leg during the Fort Hood shooting rampage. He pauses when he's asked about the mayhem, then credits a stout heritage with bringing him through the ordeal and leaving him eager for his scheduled January deployment to Afghanistan.

"I'm Irish. It hit the bone and bounced out," Foster, of Ogden, Utah, said Sunday of the bullet that tore into his left hip. His wife is uneasy about the deployment, but the 21-year-old Foster is resolute. "I'm a soldier. It's my job."

Across Fort Hood, signs point to a post on the mend after Thursday's shooting spree that killed 13 and wounded another 29. Accused gunman Maj. Nidal Malik Hasan, shot in the torso by civilian police to end the rampage, was in critical but stable condition and breathing on his own at an Army hospital in San Antonio.

Authorities continue to refer to Hasan, 39, as the only suspect in the shootings but they won't say when charges would be filed and have said they have not determined a motive.

Sixteen victims remained hospitalized with gunshot wounds, and seven were in intensive care.

Even as the community took time to mourn the victims at worship services on and off the post Sunday, Fort Hood spokesman Col. John Rossi said the country's largest military installation was moving forward with the business of soldiering. The processing center where Hasan allegedly opened fire remains a crime scene, but the activities that went on there were relocated, with the goal of soon reopening the center.

"There's a lot of routine activity still happening. You'll hear cannon fire and artillery fire," Rossi said. "Soldiers in units are still trying to execute the missions we have been tasked with."

President Barack Obama will attend a memorial service Tuesday honoring victims of the attack, amid growing suggestions that Hasan's superior officers may have missed signs that he was embracing an increasingly extremist view of Islamic ideology.

Sen. Joe Lieberman said Sunday he would begin an investigation into what the Army should have known about Hasan. A day earlier, classmates who participated in a 2007-2008 master's program at a military college said they complained to faculty about what they considered to be Hasan's anti-American views, which included his giving a presentation that justified suicide bombing and telling classmates that Islamic law trumped the U.S. Constitution.

"If Hasan was showing signs, saying to people that he had become an Islamist extremist, the U.S. Army has to have zero tolerance," Lieberman, an independent from Connecticut, said on "Fox News Sunday." "He should have been gone."